A dual exhaust system, which is typical for V8 or V6 engines, includes two parallel exhaust paths with a local interconnection that links the exhaust paths together. In a standard configuration, one exhaust path is associated with one set of engine cylinders (one set of 3 (V6) or 4 (V8) cylinders) and the other exhaust path is associated with the other set of engine cylinders (the other 3 (V6) or 4 (V8) cylinders). Each exhaust path extends from the respective set of cylinders at the engine to a separate muffler, i.e. each exhaust path extends to its own muffler. Exhaust gases exit the system through one or more outlet tailpipes. The local interconnection between the two exhaust paths is typically a balance pipe that is used to link the two paths together at a position upstream of the mufflers.
In some configurations, each exhaust path has a valve that is used to vary exhaust flow for acoustic purposes and/or for operating efficiency of the exhaust system or engine. One valve is associated with each exhaust path. The valves are of the same design and are controlled together. This type of configuration does not effectively operate to provide sufficient noise control for varying applications.